This invention relates to a coil spring shaper, particularly to one having a structure for easy operation, low cost, low energy consumption, capable to make springs of accurate size and with no excessive part, not to harm or scar material, to leave low stress, and possible to produce completely automatically.
FIG. 1a shows a spring made with a conventional flat-head coil spring shaper, and it has two hook-shaped excessive end portions a'. But the two hook-shaped excessive portions a' are to be cut off to make the spring completely finished, as common coil springs should have two ends being cut neatly, without any excessive end portions. As the excessive end portions of a finished spring not only additionally increases cost of the spring and of equipment, but wastes material, i.e. naked steel wire used for coil springs, not meeting economical gain.
Further, the conventional flat-head coil spring shaper has many rollers and other components, and coil springs made with it have a large common difference not only of length but of the inner and outer diameters.
Further, it may have other disadvantages of producing harmed and scarred finished coil springs and high stress left therein by friction caused in many processes required by the excessively complicated structure of the conventional flat-head coil spring shaper.
In addition, the conventional flat-head coil spring shaper has considerably many motors to produce large noise in producing processes. And they are generally AC ones, having to rotate idly when they are in waiting condition, wasting electricity in a large degree (servomotors may not need to rotate idly). Further, it has a large heavy table, having as much as 15 tons for shaping a coil spring of 16 mm diameter. Then it costs a great deal and results in a large disadvantage for installing or transporting.